Common Wild Petunia is a native herbaceous perennial in the Acanthus family (Acanthaceae). It is one of ten species of Ruellia documented to occur in Alabama. It occurs state wide in mesic to dry woodlands, along streams, in prairies, and on roadsides. Common Wild Petunia is a perennial that dies back to the roots each winter. The usually unbranched stems grow to a height of two feet. Several stems are often produced from the same rootstock. Common Wild Petunia has opposite simple leaves, and produce flowers from the leaf axils. The flowers are blue or lavender in color and only remain open for one day. However, the plant produces a succession of flowers from early summer through frost. Common Wild Petunia fruits are capsules that “explode” at maturity, scattering the seed. Gardeners often find volunteer seedlings some distance from the parent plant. This is one of the easiest wildflowers to grow. It tolerates or even thrives in a wide variety of soil, light, and moisture conditions. Common Wild Petunia can withstand drought and can grow and flower in deep shade. It is often available from wildflower nurseries, or can be grown from seed or stem cuttings. Seed capsules should be collected as soon as they turn brown to prevent losing the seed. Germination can be low, but the plant produces an abundance of seed. Common Wild Petunia’s blue and lavender flowers compliment the yellows and whites of many summer flowering plants. When purchasing plants from a nursery, make sure you do not get the weedy non-native and invasive Britton’s Wild Petunia or Mexican Bluebell (Ruellia simplex C. Wright Synonym Ruellia brittoniana Leonard). That species often forms large clumps from rhizomes and stems that root when they come into contact with the soil or water. It can quickly crowd out native species and has become a real pest in Florida.--A. Diamond

Specimens and Distribution

This species has been reported in the following counties by the herbaria listed. An overview of the individual specimens are provided in the table that follows. Click on the accession number to view details; click on column headers to sort; choose a county or herbaria to filter the specimen data.